In general, desirable features of interest for photodetectors include improved response times and low noise; particularly in optical systems. One type of photodetector of particular interest for use in optical systems is the avalanche photodetector (APD). Avalanche photodetectors exhibit current gain due to avalanche multiplication as discussed further in European Patent Publication No. 0150564 (hereinafter '564 Publication), published Aug. 7, 1985, entitled “Electronic Device Comprising a Heterojunction” listing as inventors F. Cappasso and A. Cho, hereby incorporated by reference as though, fully rewritten herein. The '564 Publication relates to heterojunction photodetectors including avalanche photodetectors having separate absorption and multiplication regions; particularly Group III-V compound semiconductors, such as Ga0.47IN0.53As, as the light absorbing material which is grown lattice matched to a substrate comprising a Group III-V semiconductor such as InP.